What's Happening!!

Principal cast

Roger "Raj" Thomas (Ernest Thomas), the show's protagonist, is a teenager living in Watts with his divorced mother Mabel and his younger sister Dee. Raj is an intelligent, well-mannered young man who sports large black horn-rimmed glasses and aspires to be a writer. Many episodes involve Raj taking steps to pursue his dream, from saving up for a screenwriting course or a typewriter to trying to impress a TV producer. Eventually, he graduates from high school, moves out, and attends college (ostensibly the University of Southern California). Raj is known for his trademark high-pitched laugh. Raj has some unique dance moves, such as placing his chin on his fist like “The Thinker” pose.

Frederick (Freddy) "Rerun" Stubbs (Fred Berry) is an overweight, bumbling, comedic young man, commonly seen wearing a red beret and matching suspenders. He is often teased by his friends for being overweight and unintelligent. However, Rerun is a very skilled dancer and is commonly seen entering dance contests or trying to get on TV commercials. He is nicknamed "Rerun" because, due to his failing grades in school, "every summer he has to go to school to rerun the stuff he did all winter." In the third season, Rerun shares an apartment with Raj and works as a page for ABC. His trademark phrase is "WHAT'S HAPPENING?!?!?!?!"

Dwayne Clemens Nelson (Haywood Nelson) is the youngest member of the trio. Dwayne has an unassuming, good-natured demeanor and suffers from debilitating shyness and acute fear of the dark. While Rerun attempts to enter dance contests and Roger aggressively pursues his dream of becoming a famous writer, Dwayne's plotlines often deal with his problems with girls, bullies, and uncertain future. Dwayne's character is well known for his greeting, "Hey, hey, hey!" (with an emphasis on the second "hey"). His other trademark catchphrase is when he utters "Uh-Uhn" when he denies or refuses something. Dwayne is the only character who appears in every episode of What's Happening!!

Mabel Thomas (Mabel King) is Raj's "large-and-in-charge" mother. She is typically the voice of wisdom, and the parental authority over not only Raj and Dee, but Dwayne and Rerun as well. Mabel's ex-husband drifts in and out of her life during the first season. Her role became less important in later episodes until eventually, she disappeared from the show, though her character was never really written out and still mentioned off-screen. Supposedly, King disagreed with the show's concept and direction and decided to leave the show. Her trademark phrase is "This is true" when agreeing with something said.

Dee Thomas (Danielle Spencer) is Raj's younger sibling. She personifies the typical "annoying little sister." She is bratty, keen, shrewd, and obsessed with making money, usually by blackmailing her brother and his friends a quarter at a time. As the series progressed and Dee grew older, her caustic personality mellowed into a sly sense of sarcasm. While Dee still enjoyed scamming Raj out of a quarter every so often, she became more likable and got along better with him. After Raj moved into an apartment in the third season, Dee remained in the Thomas house with waitress Shirley moving in to help out. Her trademark phrase is "Ooooohh, I'm tellin' Mama!" or "Ooooohh, you're gonna get it!" when she witnesses or hears about a wrongdoing, especially by her brother. Her favorite food is peanut butter. Her birthday is September 17.

Shirley Wilson (Shirley Hemphill) is a portly waitress at the neighborhood restaurant Rob's Place, where the main cast is regular patrons. She is a brash person who likes to take shots at the boys and most often clashes with Rerun (with both Shirley and Rerun being overweight, they exchange "fat jokes"). Some episodes turn the spotlight briefly on Shirley and her joys and sorrows. Shirley moves into the Thomas residence in the last season to be a guardian to Dee after Raj moves out and Mrs. Thomas leaves to tend to a sick relative.

Recurring characters

Bill Thomas (Thalmus Rasulala) is Mabel's ex-husband and the father of Roger and Dee. He divorced Mabel, ran out on his family, and became a shady character. When he first appears, he tries to con Mabel out of money. Later episodes in which he appears to depict him in a more positive light and culminates with his marriage to Lee Henderson (Lee Chamberlin). After his marriage, Bill was never seen again on the show, although he is mentioned. On follow-up series What's Happening Now!!, he guest starred in that show's Season 2 premiere episode "Nadine's Surprise". In that particular episode, it was explained that him and Roger had a strained relationship since he remarried and the latter's wife Nadine had planned a surprise reunion because Bill was planning to make amends with his estranged son.

Gene "Rabbit" Walker (Ray Vitte) is a political-science major at the University of Southern California, and a track-team member. He appears in two first-season episodes as a boarder at the Thomas home, renting Dee's bedroom. In his first appearance, he is referred to as "Dean" which is even written on the end credits. Gene took a liking to Dee, giving her the nickname "Small Portion". In another episode, his character is mentioned as being away (although his name was not given) so Mrs. Thomas offered his room to Dee's ex-con pen-pal.

Detective "Big Earl" Barnett (John Welsh) is a police detective who lives in the apartment building Raj and Rerun move into in the third and final season.

"Little Earl" Barnett David Hollander is Big Earl's son. He has a huge crush on Dee, who is about 5 years his senior.

Rob (Earl Billings) is the owner of Rob's Place.

Terry "Snake" Simpson (Leland Smith) is a basketball player whom Roger tutored. He eventually became a friend of Roger, Dwayne, and Rerun.

Miss Collins (Fritzi Burr) is a high-school teacher. She admired Roger but had trouble with Rerun.

Marvin (Bryan O'Dell) is the boys' high-school classmate. He was a reporter for the school paper and was sometimes seen at Rob's Place.

Leon (Henry Robinson) made two appearances as Rob's customer in "Shirley's a Mother" and as a strong arm gangster who bets on Rerun's disco dance abilities in "Disco Dollar Disaster".

Diane Harris (Debbi Morgan) is another classmate of Roger, Dwayne, and Rerun. For the first two seasons she was frequently seen in the classroom or at Rob's Place with them, and at a birthday party for Roger. (In the pilot episode, she was referred to as "Diane Stewart".)

Larry Nelson (Greg Morris) is Dwayne's father, a local politician.

Notable guest stars

• The Doobie Brothers appeared as themselves to perform a concert at Jefferson High (which was portrayed as the Doobies' alma mater), where Raj, Rerun, and Dwayne attend. Incidentally, one of the band's members (Patrick Simmons) stated he remembered Rerun from one of his old classes, saying "Glad you came back!" Rerun responded, "Came back? I'm still here!".
• Actor Theodore Wilson made three appearances on What's Happening!! as three different characters: in the pilot episode he played the father of a classmate named Betty who hosted a house party without her parents' permission; a card player alongside Mabel's employer, who gambled away his wife's jewelry but pointed the finger at Mabel as a coverup; and as bootlegging criminal Al Dunbar, who forced Rerun to illegally record the Doobie Brothers concert.
• Actress Chip Fields appeared on What's Happening!! as two different characters: Shirley's pregnant sister Norma; and Rerun's sister Donna, with whom (and her husband Ike) Rerun lived before moving in with Raj.
• The dance group The Lockers appeared in the first season as a group called "The Rockets" that Rerun auditioned to perform with on TV. (Fred Berry was an original member of the Lockers.) Wolfman Jack also made an appearance in this episode.
• Sorrell Booke, Hazzard County's corrupt commissioner Boss Hogg from The Dukes of Hazzard, appears in the Season Three episode "Basketball Brain," as an agent of the star basketball player whom Roger is tutoring.
• Actor Tim Reid appeared as Dr. Claymore in the episode "It's All in Your Head".
• Future Academy Award & Grammy Award winner Irene Cara guest-starred as Rerun's would-be immigrant bride Maria in the episode "Rerun Gets Married."
• Musician and actor Slim Gaillard appeared as Al in the episode "The Thomas Treasure" (March 16, 1979).